Is it permissible to search for another job and leave the current one, despite the existence of a penalty clause in the contract that stipulates paying a sum to the company if one leaves the job before the end of the term?

The lease contract is one of the binding contracts, and it is not permissible to terminate it except for a valid reason or with the consent of the other party. Therefore, what was mentioned is not considered an excuse that permits the termination of the contract, and adherence to the agreed-upon period is obligatory, due to the Almighty’s saying: (O you who have believed, fulfill [all] contracts) and due to the Prophet’s (peace be upon him) saying: “Muslims are bound by their conditions.”

If the management is convinced by your excuse, then they may waive their right. Otherwise, you must complete the contract, and you are obligated to pay the financial penalty if you leave the job before the end of the term without the company's consent, as stipulated in the contract.